1. Field of the Invention
The present invention relates in general to RF systems and components. More particularly the invention is directed to RF phase shifters and related methods.
2. Description of the Prior Art and Related Background Information
In various RF applications precise control of the phase of the RF signals is important. For example, in RF antenna arrays precise phase control is necessary to ensure proper phase of radiated signals for beam control applications, such as beam steering, beam tilt control and beam forming. In such applications the RF signal to be phase shifted is relatively high power and not suitable for control by conventional low power digital electronics components. Also, in applications where the radiated signal is a communications signal it is undesirable to introduce distortion which can be caused by nonlinear effects from the phase shift circuitry. These constraints severely limit the phase shift components which can be employed and typically relatively bulky and expensive mechanical phase shifters are employed.
Therefore, a need exists for an adjustable phase shifter suitable for high power RF applications such as antenna arrays.